Incidence and Clinical Impact of Anti-TNFα Treatment of Severe Immune Checkpoint Inhibitor-induced Colitis in Advanced Melanoma: The Mecolit Survey

Immune checkpoint inhibitors (ICI) significantly improve overall survival (OS) in patients with advanced melanoma, but immune-related colitis may occur and warrant anti-tumor necrosis factor alpha (TNF alpha) treatment in severe forms. A nationwide, multicenter retrospective survey was conducted to assess both, the real-life incidence of grade 3/4 ICI-induced colitis treated with anti-TNF alpha, in patients with advanced melanoma, and the consequence of this therapeutic strategy on disease outcome. All patients with advanced melanoma treated with anti-TNF alpha agents for severe ICI-related colitis in the participating centers were included. Relative incidence was calculated according to the total number of patients treated with ICI in network centers during the period of inclusion. The possible impact of anti-TNF alpha treatment on disease outcome was evaluated through comparison of objective response rate, progression-free survival, and OS with pivotal literature data. Twenty-seven patients from 13 tertiary referral centers were included. Overall, severe ICI-related colitis treated with anti-TNF alpha occurred in 1% of patients with advanced melanoma, mostly with ipilimumab. Infliximab was successfully used in all patients but 1, mostly after 1 infusion. OS and progression-free survival of 12 and 3 months, respectively, were observed in these patients, along with an objective response rate of 41% at 12 months. This survey shows a low real-life incidence of severe colitis requiring anti-TNF alpha. Response rates to immunotherapy and survival data do not appear to significantly differ from those observed in pivotal studies. Severe ICI-induced colitis requiring anti-TNF alpha treatment appears to be a rare event in advanced melanoma, and infliximab does not seem to adversely affect disease outcome.